Method of preventing conversion of photographic film used for making images of a single object

ABSTRACT

A method of preventing the home use of photographic film by employees which entails recording elongated marks thereon which are positioned between separate subareas of a film format, the subareas bearing multiple images of a single object to be photographed, such marks also aiding in the cutting steps which separate the multiple images from each other after the film is developed.

United States Patent Kuhns 51 Jan. 18, 1972 H4: M E'I'HOD OF PREVENTING CONVERSION OF PHOTOGRAPHIC FILM USED FOR MAKING IMAGES OF A SINGLE OBJECT [72] Inventor: Roger J. Kuhns, Lincoln, Mass.

[73] Assignee: Avant Incorporated, Lincoln, Mass.

[22] Filed: Nov. 10, 1969 [211 App]. No.: 875,492

[56] References Cited UNITED STATES PATENTS 1,957,864 5 1934 Tuttle et a1 i. ..96/78 x Dodge ..96/79 X Paine McCune Cummins ..95/36 X Primary Examiner-David Klein Attamey-Robert L. Nathans [5 7] ABSTRACT Claims, No Drawings METHOD OF PREVENTING CONVERSION OF PHOTOGRAPHIC FILM USED FOR MAKING IMAGES OF A SINGLE OBJECT BACKGROUND OF THE INVENTION This invention relates to the field of manufacturing photographic film. It is often desirable to employ a multiple-image camera which simultaneously records multiple images of a single object such as a person upon four rectangular subareas l 0 which just fit into a standard rectangular film fonnat. A typical multiple-image camera which utilizes Polaroid-Land" diffusion transfer photographic film and print paper is disclosed in US. Pat. No. 3,345,924 assigned to the same assignee as the present invention. A film pack is positioned at the image plane and the aforementioned rectangular film sheets are sequentially exposed. After development, the four images are separated from each other by utilizing a die-punching SUMMARY OFTHEINVENTION In accordance with the mostpreferred embodiment of the present invention, the transferprint paper is perforated along two orthogonal lines dividing the rectangular print format into four or two substantially equal subareas, each to receive a similar image of a given subject to be photographed. Instead of diecutting the print after development, the series of cuts making up each perforated line facilitates manual separation of the four images without diecutting while at the same time the perforated lines render thefilm completely useless for amateur photography since they mar the overall scene being photographed. The perforations could alternatively be on the film negative, thus preventing or distorting diffusion transfer contact of the image where perforated. This would mar the overall of cuts making up the lines should merely cut the print paper and not effect area removal of paper, since area removal of paper might allow significant amounts of viscous developer to ooze out to gum the pressure rollers in the Land" camera. The r-inch-wide pod containing the viscous developer is situated along the end of the film so that the perforations should not cut into the pod.

The aforementioned elongated marks or lines may also be photographically recorded on the film without employing perforation techniques. This approach could be implemented by positioning thin elongated sources of actinic radiation over the film format which would expose the film along thin elongated lineswhich would be positioned with respect to the negative film format to divide the format into four or, for that matter,

two subareas as was previously the case in connection with utilizing perforation techniques. As a result, thin exposed white lines would be photographically recorded upon the film format after development and would similarly render the film useless for amateur photography. Such white lines would also visually aid an operator in separating the subimages from each other through the use of scissors or a diecutter. It may be practical to utilize a thin elongated source of X-rays or radioactive material such as strontium 90 rather than a source of visible light. I v

Whileit would probably vbe most economical to mark the film during the manufacturing process, it is also conceivable that the step of marking the film could be carried out before the film is put into use and after the film is shipped from the manufacturing facility as a retrofit. The term film," utilized in the following claims, is intended to cover the negative sheet, the positive sheet, or both.

sensitized area along these perforated lines but would not offer the perforated teapot? capability.

SPECIFIC DESCRIPTION The aforementioned perforated marks or lines may be readily produced on each piece of rectangular transfer print paper by employing a conventional perforating wheel or by steel rule dies with sharp points, particularly if rounding of comers is desired. The perforating wheel would be moved across the print paper format to produce two orthogonal perforated lines dividing the film into four or two substantially equal subareas. Since the developed Land rectangular prints are surrounded by a white noninformation bearing border, it may also be desirable to surround the image-bearing print paper areas with perforated lines forming a frame or rectangle about the light-sensitive areas so that the imagebean'ng subareas may also be readily manually detached from the white border areas by the operator. Preferably, the series I claim: v

l. A method of preventing unauthorized use of photographic film utilized for photographically recording a plurality of multiple images each within an associated one of a plurality of contiguous subareas, said subareas substantially filling a given area of film, said given area having a size capable of having a single scene photographically recorded thereon by an ordinary camera during a single exposure time interval comprising the step of: I

producing at least one elongated mark upon said given area of said film prior to using the film along at least one boundary between said subareas to deter exposure of said entire given area to said single scene photographically recorded upon and substantially filling said given area of said film.

2. The process as set forth in claim 1 wherein two elongated marks are produced upon said film positioned orthogonally with respect to each other for dividing said film into a plurality of subareas.

3. The process as set forth in claim 1 wherein said marks are produced by photographically exposing thin elongated areas of said film to actinic radiation for recording said marks upon said film.

4. The process as set forth in claim 1 wherein said marks are produced by perforating said film along at least one line.

5. The process as set forth in claim 4 wherein said perforating produces a series of discontinuous cuts in said film. 

2. The process as set forth in claim 1 wherein two elongated marks are produced upon said film positioned orthogonally with respect to each other for dividing said film into a plurality of subareas.
 3. The process as set forth in claim 1 wherein said marks are produced by photographically exposing thin elongated areas of said film to actinic radiation for recording said marks upon said film.
 4. The process as set forth in claim 1 wherein said marks are produced by perforating said film along at least one line.
 5. The process as set forth in claim 4 wherein said perforating produces a series of discontinuous cuts in said film. 